Greetings Vortex-L. Normally..most Mars "speculation images" are not worth noting and of poor content, but IMHO this is an exemption.
http://www.examiner.com/article/mars-evidence-of-intelligent-design-earth-valve-found-nasa-image-report There could be a simple earth fabricated valve explanation. Note: give the video a few seconds to see the machined circle. Ad Astra, Ron Kita, Chiralex
